# Analysis of a vacuum sealed foil baggie



## RJpuffs (Jan 27, 2008)

I was curious, and unlike the feline that met its untimely end due to it, I attempted to disassemble an Esoterica foil baggie.

The other discussion(s) about storage media had me thinking about this. Will such a bag really work for aging? Anecdotal accounts suggest so, and a post that I read some time ago by GLP suggested that several layers were used in these foil bags to provide the same air/moisture proofing as a tin or jar.

After I finished moving the contents of this baggie into mason jars, I cut out a chunk of the baggie, took a razor blade and attempted to separate the layers. Wasn't easy, this stuff is well night bulletproof.

I wish I had a good macro lens for the camera to take pics, but I don't, so here is a text only analysis.

There are indeed several layers. I found three. The inside is an almost clear plastic film, I would guess a mylar sheet 3mil thick (I've worked with these before in a previous life/career), its more rigid than a ziplock bag. Laminated to it is a metallic film, feels like a very thin sheet of aluminum foil (like the stuff you have in the kitchen) but it may be metallized nylon (like party balloons). On top of that (the outside of the bag) appears to be another laminant though I am unable to separate it (too damn thin). This is the classic yellow-ish color of the bag. The printing may be inside the top layer, I was unable to scratch the letters or the yellow off, I'm thinking reverse printed plastic film laminated onto the metallic foil. Or the top two layers may be a classic party balloon structure (one piece).

Mylar is used for airtight seals among other things. Party balloons (metallized nylon) are also somewhat airtight (they do go flat eventually, but I suspect it is the seal that gives on balloons). Does this combination work to keep both O2 and H20 molecules contained/isolated? Do we have a scientist in the house?


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## commonsenseman (Apr 18, 2008)

Interesting analysis Ron, I'll be watching to see what scientists have to say about this. 

I guess my only other concern would be whether the bag could impart a plastic flavor over time (even if not by the bag, perhaps by the little plastic tray).


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## phatmax (Mar 18, 2009)

commonsenseman said:


> Interesting analysis Ron, I'll be watching to see what scientists have to say about this.
> 
> I guess my only other concern would be whether the bag could impart a plastic flavor over time (even if not by the bag, perhaps by the little plastic tray).


At least the MYLAR MSDS sheets make it seem that it is very stable and non-leaching.


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## SmoknTaz (Jun 18, 2008)

Very interesting Ron, thanks for the insightful read. Perhaps some here have already been using this method to age? Anyone?


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## plexiprs (Nov 18, 2005)

Mylar ballons limp-out due to the poor sealing mechanisms used and the fill is Helium which leaks out of many things that air or water-vapour wouldn't.... Nice info!! Well done!!


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